Method of fabricating barbed tape

ABSTRACT

A process for manufacturing barbed tape from strip without scrap loss. The first step in manufacture is slitting the edges of the strip to form points. The points are uncovered either by elongating the tape or by bending portions of the edges of the tape.

Umted States Patent 1 [111 3,763,529 Mus rave Oct. 9, 1973 [54] METHOD OF FABRICATING BARBED TAPE 2,908,484 10/1959 Uhl 256/8 W61 Iavaaaaa Dania Maaaaava 8201 Caraway 53221 33 $51323 $555511... 1;. ...jj"1i375 Cabm Johna 20731 3,224,736 12/1965 Musgrave 140/58 [22] Filed: Feb. 10, 1972 [21] APPL No; 225,328 Primary ExaminerLowell A. Larson [52] US. Cl 29/7.l, 140/58, 256/8 [57] ABSTRACT [51] Int. Cl B2lf 25/00 [58] Field of Search 29/7 1 7 2 7 A process for manufacturing barbed tape from strlp f l without scrap loss. The first step in manufacture is slitting the edges of the strip to form points. The points [56] References Cited 7 are uncovered either by elongating the tape or by bending portions of the edges of the tape. UNITED STATES PATENTS 310,813 l/1885 Ford 29/7.l 8 Claims, 10 Drawing Figures METHOD OF FABRICATING BARBED TAPE This invention relates to barbed tape for use in barricades and entanglements employed as fences or obstacles, particularly in military operations. Common barbed wire has been widely used for such purposes but it is awkward to transport because even when wound on a bobbin, many of the barbs are exposed.

Flat strips or tapes with barbs along their edges have the distinct advantage that they can be coiled on a reel. In this compact form they occupy relatively little space and the sides of the reel cover the barbs. Such strips or tapes are adapted for longitudinal twisting when installed in the obstacle in order to orient the barbs in various directions.

The principal object of this invention is to provide a method of fabricating barbed tape.

Another object is to provide a method of fabricating barbed tape with minimum scrap loss.

Another object conservation to provide a method of fabricating barbed tape with a minimum of labor and machinery.

These and other objects and advantages of the present invention will become apparent upon consideration of the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. I shows a partly fabricated tape according to the present invention.

FIG. 2 shows a tape fabricated according to the present invention, with barbs exposed.

FIGS. 3 and 4 show a tape fabricated according to the present invention, crimped to a reinforcing material.

FIGS. 5 and 6 show a tape fabricated according to the present invention, welded to a reinforcing material.

FIG. 7 shows a tape fabricated according to the present invention, twisted longitudinally.

FIG. 8 shows a plurality of tapes fabricated according to the present invention, to indicate how they may be fabricated from a single strip or sheet of material.

FIG. 9 shows a tape fabricated according to the present invention, coiled for transportation or storage.

FIG. 10 is a schematic view to illustrate a step by which tape as shown in FIG. figures, can be made into tape as shown in- FIG. 2.

Referring to the drawings there is shown in all views a tape 11 which may be of any suitable material. As shown in FIG. 1, slits 13 are formed along the edges of tape 11 by any suitable method. The slits are at an acute angle relative to the edges of the tape. Along either edge of the tape, the angles thus defined have their vertices positioned'alternately toward one or the other end of the tape.

Each slit on one edge of the tape has a substantially parallel counterpart slit on the other edge of the tape, and each slit is positioned along the tape at a location substantially opposite its counterpart on the other edge.

On FIGS. 1 and 2, the area of thetape between each slit and its counterpart is identified by numeral 15. In

To indicate that the holes are an alternate feature, which may or may not be used in a given instance of fabrication, they are shown on the right portion of the tape illustrated in FIGS. 1 and 2, but not on the left portion.

The tape shown in FIG. 1 can be deformed to the shape shown in FIG. 2 by subjecting it to a force tending to elongate it along its longitudinal axis. One method of applying such a force is shown in FIG. 10.

FIG. 10 illustrates schematically the passing of tape 11, slit as shown in FIG. I, through a machine having two pairs of rollers turning at substantially the same speed. The tape is moving generally from A toward B, as indicated by the arrow, and is gripped by each pair of rollers. It may be noted that rollers R and R are greater in diameter than rollers RR and RR. As both pairs are turning at the same speed, tape at A is moving faster than tape at B, and a stretching effect occurs as the tape moves from the first pair of rollers to the second pair.

Because of slits I3, tape 111 is no longer symetrically integral about its longitudinal axis. Referring to FIG. 1 it can be seen that each longitudinally integral portion is offset from the centerline of the original tape, and that such portions are displaced alternately to one side or the other along the length of the tape, each being connected to the next by an area 15. Obviously the centerline of the integral tape is not a straight line but a series of offset parallel lines connected by angular lines,

When therefore, the tape shown in FIG. 1 is stretched longitudinally by the method illustrated in FIG. 10, or any equivalent method, it will be deformed to substantially the shape shown in FIG. 2. This is because the centerlines of the several adjacent portions which make up the tape meet at angles. A tensile force applied longitudinally along the tape will tend to bring these centerlnes into alinement, thereby deforming each slit 13 into an angular opening 13a. Opening the slits exposes the barbs.

It is not intended to limit the present disclosure as to materials, dimensions or precise geometry. It is readily apparent that the principle may be applied to tape varying in detail from that shown.

Tape may also be used with reinforcement. FIGS. 3 and 4 show tape 11 crimped to a wire 23. Portion 25 of the tape is bent around the wire thus exposing edge 13b of barbs 21. The tape thus crimped may be either that shown in FIG. 1 or that shown in FIG. 2.

The tape may also be welded to a reinforcing wire, as shown in FIGS. 5 and 6. Tape as shown in FIG. 2 is fixed to wire 23 by weld 27, which is illustrative only. Any known welding method may be used.

FIG. 7 shows tape, after deforming to the shape shown in FIG. 2, twisted about its longitudinal axis so as to orient the barbs at various radial angles; FIG. 9 shows tape coiled into a' roll for transport or storage.

FIG. 8 shows how the stretching process described for FIG. 10 may be used to fabricate a plurality of tapes side-by-side simultaneously. After stretching, the tapes are cut apart along broken line 29 Tape made as described may be subjected'to further well-known processes to modify physical properties, add protective coating, or otherwise improve the product. It is also possible to practice the invention by issuing tape as shown in FIG. 1 to the user. After installing the tape in the obstacle he may twist and elongate it, by

the Spanish windlass method, into the shape shown in FIG. 7.

The Spanish windlass is a well-known method of tensioning a rope by using a spike or a stick as a lever. The rope is looped once around the stick, and then the stick is revolved around the loop in a plane parallel to the length of the rope, thus tensioning it. The same method can be applied to barbed tape.

What I claim is:

1. A method of fabricating barbed tape comprising: forming a plurality of slits intersecting one edge of a tape of flexible hard deformable material at an acute angle with but not extending to the longitudinal centerline of said tape, each successive slit being oppositely inclined relative to said centerline; forming on the other edge of said tape at a position substantially opposite each of said slits a similar parallel slit, whereby the successive integral portions of said tape do not lie in a straight line; and elongating said tape thereby displacing pointed portions of said tape away from said centerline.

2. The method set forth in claim I further characterized by the stated operations being performed simultaneously on more than one tape.

3. The method set forth in claim 1 further characterized by an operation for affixing reinforcing means to said tape after elongating.

4. The method set forth in claim 1 further characterized by the use of machinery to elongate said tape.

5. The method set forth in claim 1 further characterized by the said elongating being accomplished manually by the step known as the Spanish Windlass.

6. The method set forth in claim 1 further characterized by an operation for coiling said tape into a coil, after elongating.

7. The method set forth in claim 1 further characterized by an operation for twisting said tape about its longitudinal axis, after elongating.

8. The method set forth in claim 1 further characterized by the forming of holes in said tape before elongat ing thereby making it easier to deform. 

1. A method of fabricating barbed tape comprising: forming a pluraLity of slits intersecting one edge of a tape of flexible hard deformable material at an acute angle with but not extending to the longitudinal centerline of said tape, each successive slit being oppositely inclined relative to said centerline; forming on the other edge of said tape at a position substantially opposite each of said slits a similar parallel slit, whereby the successive integral portions of said tape do not lie in a straight line; and elongating said tape thereby displacing pointed portions of said tape away from said centerline.
 2. The method set forth in claim 1 further characterized by the stated operations being performed simultaneously on more than one tape.
 3. The method set forth in claim 1 further characterized by an operation for affixing reinforcing means to said tape after elongating.
 4. The method set forth in claim 1 further characterized by the use of machinery to elongate said tape.
 5. The method set forth in claim 1 further characterized by the said elongating being accomplished manually by the step known as the Spanish windlass.
 6. The method set forth in claim 1 further characterized by an operation for coiling said tape into a coil, after elongating.
 7. The method set forth in claim 1 further characterized by an operation for twisting said tape about its longitudinal axis, after elongating.
 8. The method set forth in claim 1 further characterized by the forming of holes in said tape before elongating thereby making it easier to deform. 